The present invention relates in general to removing particles from gases, and in particular to a new and useful ultra-high particulate collection apparatus and method.
Venturi scrubbers have been used for particulate collection for at least 60 years. The use of venturi scrubbers for particulate collection from coal fired gasifiers is known and has been proposed for use on black liquor gasifiers. Electrostatic precipitation is also well established for fine particulate control. Electrostatic agglomerators are less well known. A form of electrostatic agglomeration is used in the carbon black industry to facilitate the collection of soot sized particles on fabric filters. The use of electrostatic precipitation on fuel gas or synthesis gas from gasifiers has been proposed in the literature but has not actually been commercialized. No prior art is known which proposes use of two venturi scrubbers in combination with an electrostatic agglomerator for the cleanup of any gas borne particulate.
An electrostatic agglomerator/venturi scrubber combination was developed in the 1960's. In the 1960's a Kraft process was operated in the United States with a combination of an electrostatic agglomerator upstream of a single venturi scrubber. The Kraft process is under much less pressure and has much lower particle loading than the output of a black liquor gasifier and would provide the person having ordinary skill in this art with no motivation to include a second upstream venturi scrubber for any purpose.